Light therapy device and method of use

ABSTRACT

A light therapy device is taught including a light emitting assembly having light emitting diodes (LEDs) as a light source. The light emitting assembly capable of generating 2,500 lux to 7,500 lux at 12 inches.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 10/980,272 filed Nov. 4, 2004, which is presently pending. U.S.application Ser. No. 10/980,272 is a continuation of U.S. applicationSer. No. 09/710,782 filed Nov. 13, 2000, now U.S. Pat. No. 6,875,225issued Apr. 5, 2005. The parent applications and the present applicationclaim priority to Canadian patent application No. 2,300,569 filed Mar.14, 2000 and to Canadian patent application No. 2,317,319 filed Aug. 30,2000.

FIELD OF THE INVENTION

The present invention relates to a light therapy device and inparticular to a light therapy device for treatment of light deficientdisorders.

BACKGROUND OF THE INVENTION

There is much support for the use of light therapy to overcome lightdeficient disorders. It has been proven that treatments involvingshining light directly towards a patient's eyes will alleviate or curelight deficient disorders including Seasonal Affective Disorder (SAD),circadian sleep disorders and circadian disruptions associated withjet-lag, shift-work, PMS and bulimia.

There are two types of light therapy devices presently available. Onetype of device is large in size and floor or desk mountable. Thesedevices include light sources of fluorescent bulbs. Although they can bemoved from one position to another, they are not generally portable. Inaddition, the light source is quite fragile. The second kind of lighttherapy devices is head mountable. These devices are formed aseyeglasses or visors. While they are portable, they are not generallyaccepted by patients for use in public because of their odd appearancewhen worn on the head. This combined with safety concerns about eyedamage given the proximity of the light source to the eye, has resultedin head mountable treatment devices failing to be generally accepted asa light therapy device.

These devices therefore are of limited use for persons requiring aportable and discreet treatment device. A light therapy device is neededfor use by, for example, the business traveler that is portable andaesthetically appealing.

SUMMARY OF THE INVENTION

The present invention provides a portable and lightweight hand-heldlight therapy device. The device is durable, being resistant to damageby normal transport. The device uses light emitting diodes (LEDs) as asource of light. LEDs offer a light source that is lightweight, small insize, simple, durable as well as energy efficient. The device is usefulfor travel and for in-flight use while being aesthetically acceptable.

In accordance with one aspect of the present invention, there isprovided a light treatment comprising: an outer housing including aopening; a light emitting assembly in the housing and operable to emitlight through the opening in the housing, the light emitting assemblyincluding a plurality of LEDs capable of generating 2,500 lux to 7,500lux at 12 inches.

The LEDs include at least some capable of emitting white-light. In oneembodiment, the LEDs are arranged in a pattern over an area and thelight emitting assembly is selected to emit light from the LEDs along asubstantially straight line directly toward the user. Preferably, adiffuser screen of light diffusing sheet material is positioned over theLEDs to provide a more uniform emission of light. While LEDs do not emitany significant amount of ultraviolet radiation, the diffuser sheetmaterial can include a UV filter, if desired.

The outer housing can include a first member and a second member, thefirst member and the second member being releasably locked together andthe light emitting assembly being storable in the first member and beingmountable on the housing such that the housing acts as a base to supportthe light emitting assembly. In one embodiment, the first and secondmembers are pivotally connected and openable in a manner similar to abook. The first and second members, when closed enclose an innercompartment accessible by opening the first and second members abouttheir pivotal connection. The light emitting assembly is storable in theinner compartment. In this embodiment, the light emitting assembly canbe mountable on the first member and the second member can act as abase.

To facilitate therapy using the device, the housing can also accommodatea therapy calculator for determining a treatment regime based on aninput of information.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation view of a light therapy device according tothe present invention. A portion of the device has been cut away tofacilitate illustration of internal components.

FIG. 2 is a side elevation view of the light therapy device of FIG. 1with the support leg folded against the housing.

FIG. 3 is a sectional view along line A-A of FIG. 1.

FIG. 4 is a side elevation view of another light therapy deviceaccording to the present invention in a closed configuration.

FIG. 5 is a side elevation view of the device of FIG. 4 in an openconfiguration, ready for use.

FIG. 6 is a front elevation of the device and configuration of FIG. 5.

FIG. 7 is an elevation of a device for permitting mounting of a lighttherapy device in a passenger compartment of a vehicle. The device isaligned for insertion into a power port of a vehicle and a light therapydevice is aligned for insertion into the docking bay of the device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1 to 3, a light therapy device according to oneembodiment of the present invention is shown. The device is small insize and resembles a large calculator or hand-held computer. Preferably,the outside dimensions of the device are less than about 7 inches wide,7 inches high and 1.5 inches deep. The size can be varied as desired andwith consideration as to portability, convenience and the componentsthat must be contained therein.

The device includes an outer housing 10. The housing is preferablyformed of a durable, impact resistant material such as, for example, apolymer (i.e. nylon, thermoplastic or blends thereof). Preferably, allhousing parts are of minimal thickness to provide suitable impactresistance and support for internal components while minimizing theweight of the device. The housing can be formed, as shown, in partssecured together by screws 12 or other fastening means.

The housing carries a light emitting assembly 20. The light emittingassembly is mounted in the housing such that in operation light emittedtherefrom is directed out through an opening 22 in the housing.

Light emitting assembly 20 includes a printed circuit (PC) board 26providing electrical connection for light emitting diodes 28. The LEDsare spaced apart on the board, with consideration as to their lightoutput and wavelength, such that the assembly emits a light ofillumination adequate for treatment of light deficient disorders. Inparticular, the light emitting assembly generates adequate illuminationfor treatment of light deficient disorders including Seasonal AffectiveDisorder (SAD), circadian sleep disorders and circadian disruptionsassociated with jet-lag, shift-work, PMS and bulimia, which is between2,500 and 7,500 lux, and preferably between about 3,500 and 5,500 lux at12 inches from the assembly. To generate this level of illumination, theassembly generally includes between about 10 and 150 LEDs togetherhaving a total light output of between 50 and 500 candelas andpreferably about 250 to 450 candelas. The number of LEDs in the lightemitting assembly may be reduced considerably as the efficiency of a LEDis increased.

Using a light therapy device according to the present invention,treatments of acceptable duration can be administered. As an example,treatments for SAD can be completed in ¼ to 4 hours and in most cases, ½to 3 hours.

For bright-light therapy, preferably white LEDs are used. However, it issometimes useful to combine light of different wavelengths and in someinstances to approximate the spectral properties or distribution of atropical sunrise. Therefore, LEDs 28 can be entirely of the typeemitting white light or, alternatively, LEDs emitting light of variouswavelengths (i.e. red or amber) can be used with white light emittingdiodes. The light generated by the light emitting assembly is preferablyconstant, though it may also be pulsed.

In one embodiment, a diffuser screen 32 is mounted over the diodes tocreate a more uniform, less harsh light emission. Preferably, LEDs 28are mounted a suitable distance from diffuser screen 32 such that thelight emitted by each LED overlaps on the screen and avoids theappearance of individual points of light behind the screen. If adiffuser screen is used, it is necessary to ensure that adequate levelsof light, as set out above, are passed therethrough to permit treatment.

Power is supplied to the LEDs through electrical lines 34. Power can beprovided through batteries or preferably, to reduce weight, through ajack 36 for connection to a 120 v electrical supply (for use in NorthAmerica). The device preferably operates using DC power and is suppliedwith an external AC-DC converter. Since the device is particularlyuseful during long distance travel in the treatment of jet lag, anadapter can be provided within the device or separately for devicecompatibility with foreign voltages of AC power or with DC power, as isprovided through power ports mounted in aircraft armrests.

To facilitate light treatment, a support leg 40 can be provided forsupporting the housing in a propped position such that light is emittedin a generally horizontal direction. In one embodiment, support leg 40is connected by a hinge 42 to the rear of the housing such that the legcan be rotated between a supporting position and a stored positionagainst the rear of the housing. A more complex stand for elevating thelight illuminating assembly can be used, as desired.

The light treatment device can be mounted in a vehicle passengercompartment including, for example, a passenger or operator seat area.The vehicle can be, for example, an aircraft, a train, a bus, a truck oran automobile. In one embodiment, the light treatment device is mountedin an aircraft seat back or in an aircraft seat armrest for use by airtravelers. The device can be mounted in a manner similar to aircrafttelephones, individual video monitors, and other such devices, whereinthe light treatment device is attached to an adjustable extension arm,thereby enabling the user to remove the light treatment device from anarmrest and position it appropriately for treatment. Alternately, thelight treatment device may be temporarily removed from its seat backmounting position and positioned on a tray table or other surface fortreatment, while remaining secured to the seat back by means of a cablethat could also serve as a power source. The device may also be mountedinto an airliner flight deck or other such areas of an airliner toprovide discreet and convenient light treatments for pilots, flightattendants and other such on-board crew affected by jet lag and fatigue.

In another embodiment, the light treatment device can be mounted in thepassenger compartments of vehicles, for example, automobiles, transporttrucks, buses, trains, and other such vehicles, wherein the device isstored when not in use but readily available to provide a light therapytreatment. In the case of automobiles and trucks, the device may bemounted on the underside of a sun visor, or within the glovecompartment, or under the vehicle's dashboard. In the latter twoexamples, the device can be attached to an adjustable extension arm inorder to permit proper positioning for treatment.

The device may also be mounted so as to provide a light treatment forthe driver or operator of these vehicles, with appropriate precautionsbeing indicated for safe operation of the vehicle, for example, at thosetimes when the vehicle is parked or idle. One such embodiment isdescribed hereinafter with reference to FIG. 7.

Housing 10 can also be formed to accommodate other electronics,batteries etc. or to define storage space such as for cords, adapters,glasses or other items. The housing can also include a cover or a case.Referring to FIGS. 4 to 6, a light therapy device according to anotherembodiment of the present invention is shown. The device has an outerhousing including an upper housing member 110 and a lower housing member112. The housing members are connected by a hinge 114 that permits themto pivot relative to each other between a closed position shown in FIG.4 and an open position shown in FIGS. 5 and 6. When in the closedposition, the housing members can be releasably locked together by acatch 116. The device is small in size and, when closed, resembles aportable compact disc player or a make-up compact.

The housing encloses a light emitting assembly 20. In the illustratedembodiment, light-emitting assembly 20 is mounted in the upper housingmember. The light emitting assembly is mounted on the inwardly facingportion of the upper housing member so that, when the device is in theclosed position, assembly 20 is protected within the housing members. Inthis way, the light emitting assembly, which is more fragile than thehousing, is protected against damage during transport.

The device is opened for use to administer a light treatment. In apreferred embodiment, upper housing member 110 unfolds from the closedposition by rotating about hinge 114. Lower housing member 112 acts as abase for supporting the light emitting assembly. Preferably, hinge 114is of the type that permits self-locking in at least a few rotationalorientations. The use of such a hinge permits that, for example, upperhousing member can be oriented to direct the light downwardly,horizontally or, if preferred, in other directions. This is useful as itmay be necessary, depending on the treatment, to have the light directedinto the patient's eyes or alternately downwardly toward a workspace.

Counterweights (not shown) can be mounted in the lower housing member toprevent the device from tipping. Member 112 can also be formed toaccommodate electronics, batteries etc. or to define storage space suchas for cords, adapters, glasses or other items. Member 112 can alsoaccommodate a treatment calculator, as will be described hereinbelow.

In one embodiment illustrated, for example in FIGS. 1 to 3, housing 10also accommodates a calculator including a display 82, a key pad 84 anda processor mounted within housing 10. The calculator is programmed tocalculate a light treatment regime based on input of information. Thecalculator processor uses calculation references such as that known asthe Jet Lag Calculator™ available from Bio-Brite, Inc., Maryland. In oneembodiment, the calculator can be used to calculate light treatmentregimes for jet lag based on inputs of information, as follows:

Option 1

-   -   i. Number of time zones crossed during trip    -   ii. Direction of time zones crossed (East or West)    -   iii. Normal wake-up time of patient (for establishing the        patient's “body clock”)        Option 2    -   i. Departure city    -   ii. Arrival city    -   iii. Normal wake-up time of patient

Based on the input of the above-noted information, the calculator willthen calculate and display a treatment regime including, for example, aperiod of light exposure and a period of light avoidance. In option 2,the calculator determines the number of time zones through which travelwill occur and uses this to calculate treatment regime. The calculatorin one embodiment calculates a two-day treatment regime.

In one embodiment, the calculator keypad includes keys to be depressedwhen inputting particular information. As an example, the keypad caninclude keys such as: “departure city”, “destination city” and “wake uptime”. The calculator can be adapted to prompt the patient such as bydisplaying questions requesting the appropriate information. Preferably,the calculator includes a pause function capable of recording a time oftreatment interruption and capable of outputting from memory the portionof the treatment remaining when treatment is resumed.

In addition or alternately, the calculator can be programmed forcalculation of other treatment regimes such as, for example, fortreatments to alleviate fatigue in shift workers. Treatments for shiftworkers may include inputs such as work shift start time, previous shifttime and normal waking time.

A speaker 88 is preferably provided for communication to the user. As anexample, the speaker can communicate with the calculator processor toaudibly prompt a user to input information. In addition, the speaker canfunction to emit an audible signal, such as an alarm, to alert a user tocommence or modify a treatment. In one embodiment, the calculatorprocessor controls a switch for the light emitting assembly such that itis turned on or off in response to a signal from the processor.

In a preferred embodiment, the calculator memory is capable of storingprevious treatment regimes. These stored treatment regimes can berecalled from processor memory for repeat trips or shift work schedules.

If desired, to enhance the usefulness of the device, the calculator canalso be programmed with other information including a clock, a standardmathematical calculator or other information such as an address book,etc.

As noted hereinbefore, a light therapy device according to the presentinvention can be mounted in a vehicle for use by passengers. One suchembodiment is illustrated in FIG. 7. A vehicle mounting adaptor 50useful for mounting a light treatment device in a vehicle passengercompartment acts as an interface between the vehicle power port 52 (i.e.an in-dash cigarette lighter) and the light treatment device 54. Inparticular, at one end the adaptor has a power port contactor 56 forinsertion into the power port. A locking collar 57 is threadedly engagedat the outboard end of the contactor 56. Once power port contactor 56 isinserted into power port 52, locking collar 57 can be tightened downabout the port by threaded advancement to reinforce the engagementbetween port 52 and power port contactor 56.

At the opposite end, the adapter includes a docking port 58 with arecess 59 having therein electrical contactors 60. The light treatmentdevice is mountable in the recess of docking port 58 in electricalcommunication with contactors 60. Venting slots 64 are formed throughthe docking port and positioned to substantially align with the vents 66on light treatment device 54 to provide ventilation to the lighttreatment device therethrough.

Power cables (cannot be seen) extend between ends 56 and 58 to provideelectrical communication therebetween. The power cables are housedwithin a bendable arm 68 of the type including a corrugated tube andinternal supports that can be bent into various orientations and, oncepositioned, will hold fast in that orientation. Arm 68 is bendable yetrigid enough to hold the weight of the light treatment device 54 anddocking port 58 without moving out of the bended configuration intowhich it has been adjusted. Locking collar 57 also securely holds powerport contactor 56 in power port 52 even against the weight of the lighttreatment device and against the stress of bending arm 68. Adapter 50can be removed from power port 54 and stored when not required.

Numerous modifications, variations and adaptations may be made to theparticular embodiments of the invention described above withoutdeparting from the scope of the invention as defined in the claims.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:
 1. A method for treating auser with a light deficient disorder using an ocular light therapydevice including: an outer housing configured for portability and handheld operation with a width of less than about 7 inches, a height ofless than about 7 inches and a depth of less than about 1.5 inches, thewidth and the height defining dimensions of a front face; a support forsupporting the housing in a treatment position on a support surface; alight emitting assembly in the housing and operable to emit lightthrough the face of the housing, the light emitting assembly includingan LED light source including 10 to 150 LEDs and configured to generatean output of light suitable for ocular light therapy of a lightdeficient disorder; a diffuser screen of light diffusing sheet materialpositioned to diffuse light from the LED light source passing from theface; and a treatment selector on the outer housing for selecting atreatment regime; the method comprising: turning on the device to causethe LEDs to be illuminated and light to be emitted from the front face;actuating the treatment selector to select a treatment regime; and withthe ocular light therapy device into a treatment position spaced fromthe eyes of the user, directing the light emitted from the LEDs towardthe eyes of the user to administer an ocular light treatment until thelight emitting assembly is turned off, wherein the device is hand-heldduring at least one of turning on, actuating and directing.
 2. Themethod of claim 1 wherein the emitted light has an intensity of 50 to500 candelas.
 3. The method of claim 1 further comprising pausing andresuming the ocular light treatment.
 4. The method of claim 1 whereinthe light is administered for ¼ to 4 hours for the ocular lighttreatment.
 5. The method of claim 1 wherein the treatment regimecomprises a period of light exposure.
 6. The method of claim 5 whereinthe treatment regime further comprises a period of light avoidance. 7.The method of claim 1 further comprising a memory configured to storethe treatment regime.
 8. The method of claim 1 further comprisingsetting the treatment regime using the treatment selector.
 9. The methodof claim 1 wherein the light deficient disorder is a circadian sleepdisorder.
 10. The method of claim 1 wherein the light deficient disorderis a circadian disruption.
 11. The method of claim 1 wherein the lightdeficient disorder is Seasonal Affective Disorder.
 12. The method ofclaim 1 wherein the light deficient disorder is jet lag.
 13. The methodof claim 1 wherein the light deficient disorder is bulimia.
 14. Themethod of claim 1 wherein the light deficient disorder is PMS.